Data Storage Devices (DSDs) are often used to record data onto or to reproduce data from a storage medium. One type of storage medium includes a rotating magnetic disk, such as in a Hard Disk Drive (HDD) or a Solid-State Hybrid Drive (SSHD). In such DSDs, a head is positioned in relation to a disk to magnetically read and write data in tracks on a surface of the disk. The head is typically located on a distal end of an actuator moved by a Voice Coil Motor (VCM).
The amount of data that can be stored on a disk in a given area (i.e., an areal density) generally continues to increase with each new generation of DSDs that use a disk to store data. New technologies have been introduced or are in development to allow DSD heads to write more data in a given area using various energy-assisted recording techniques. Such energy-assisted recording techniques can include Thermal Fly-Height Control (TFC), Heat Assisted Magnetic Recording (HAMR), and Microwave Assisted Magnetic Recording (MAMR).
TFC uses a heater on the head to adjust a fly-height of the head over the disk to allow the head to get closer to the disk when writing data to increase the storage density. HAMR uses a laser diode on the head to heat a small region of the disk that is to be written by the head. The heating of the disk temporarily lowers the coercivity of grains in the disk to allow the grains to become magnetized by the head, before returning to a higher coercivity after cooling off. This allows the use of smaller grains (and thus a higher storage density) that require a higher coercivity to remain magnetized after being written due their smaller size. MAMR uses a Spin Torque Oscillator (STO) on the head to generate a microwave field that allows the disk to be more easily magnetized with a lower magnetic field so that a higher storage density can be achieved.
However, the use of energy-assisted recording techniques can decrease the usable life of the head. In some cases, the decreased life of the head can be due to the degrading or deterioration of components in the head caused by heating. In other cases, the decreased life of the head can be due to a smaller distance or fly-height between the disk and the head, causing increased friction or wear on the head. A lowered fly-height can also increase the accumulation of disk lubricant or other particles on the head due to forces from air pressure, electrostatic forces, and/or intermolecular forces. Such accumulation of lubricant or particles on the head can interfere with the reliable reading or writing of data by the head. Accordingly, the usable life of heads in new DSDs will be shortened due to the emerging use of energy-assisted recording techniques and the continued need to reduce the head-disk interface spacing. In addition, the increased amount of data stored on disks will increase the amount of data that needs to be written or read by each head.